Mama keeps on complaining about her eyes. She said that she can't clearly see us. Everywhere she looks, she sees glare. She forces to open wide her tiny eyes each waking morning, because opening it is such a struggle. Going to the doctor is the best way to know what causes the pain in her eyes.
Astigmatism usually occurs when the front surface of the eye, the cornea, has an irregular curvature. Normally the cornea is smooth and equally curved in all directions and light entering the cornea is focused equally on all planes, or in all directions. In astigmatism, the front surface of the cornea is curved more in one direction than in the other. This abnormality may result in vision that is much like looking into a distorted, wavy mirror. The distortion results because of an inability of the eye to focus light rays to a point.
If the corneal surface has a high degree of variation in its curvature, light refraction may be impaired to the degree that corrective lenses are needed to help focus light rays better. At any time, only a small proportion of the rays are focused and the remainder are not, so that the image formed is always blurred. Usually, astigmatism causes blurred vision at all distances. Some people with very high degrees of astigmatism may have cornea problems such as keratoconus.
Astigmatism is very common. Some experts believe that almost everyone has a degree of astigmatism, often from birth, which may remain the same throughout life. The exact reason for differences in corneal shape remains unknown, but the tendency to develop astigmatism is inherited. For that reason, some people are more prone to develop astigmatism than others.
- Distortion or blurring of images at all distances
- Headache and fatigue
- Squinting and eye discomfort or irritation
The symptoms described above may not necessarily mean that you have astigmatism. However, if you experience one or more of these symptoms, contact your eye doctor for a complete exam.
Treatment
If the degree of astigmatism is slight and no other problems of refraction, such as nearsightedness or farsightedness, are present, corrective lenses may not be needed. If the degree of astigmatism is great enough to cause eyestrain, headache, or distortion of vision, prescription lenses will be needed for clear and comfortable vision.
The corrective lenses needed when astigmatism is present are called Toric lenses and have an additional power element called a cylinder. They have greater light-bending power in one axis than in others. Your eyecare professional will perform precise tests during your eye examination to determine the ideal lens prescription. Refractive surgery may be able to correct some forms of astigmatism.
Astigmatism may increase slowly. Regular eye care can help to insure that proper vision is maintained. You may have to adjust to wearing eyeglasses or contact lenses if you do not wear them now. Other than that, astigmatism probably will not significantly affect your lifestyle at all.
taken from the The University of Michigan Kellog Eye Center Research...
http://www.kellogg.umich.edu/patientcare/conditions/astigmatism.html
2 comments:
Your mom is not alone, Yanee. :) I have astigmatism too. I think you've seen me wore my glasses, right? It means I'm having that painful eye attack. hehe... I had it since I was fourth year high school. I'm just not too keen on wearing my glasses, even contact lenses. Hope your mom will be okay na.
Lots of people have astigmatisms. Eye issues in general stink. I am simply nearsighted which means I can't see far. I wear contacts and I couldn't imagine not being able to do so. However, they can be such a pain. ONce I had eye problems so bad that I couldn't even watch the tv. It hurt that badly!! The doctor said my contacts had caused me to get thousands of tiny little holes in my eye - like someone had taken a needle to them!! Yikes!!!
Astigmatism means that the cornea is oval like a football instead of spherical like a basketball. Most astigmatic corneas have two curves – a steeper curve and a flatter curve. This causes light to focus on more than one point in the eye, resulting in blurred vision at distance or near. Astigmatism often occurs along with nearsightedness or farsightedness.
Astigmatism aberrations are similar to comatic aberrations, however these artifacts are not as sensitive to aperture size and depend more strongly on the oblique angle of the light beam. The aberration is manifested by the off-axis image of a specimen point appearing as a line or ellipse instead of a point. Depending on the angle of the off-axis rays entering the lens, the line image may be oriented in either of two different directions, tangentially (meridionally) or sagittally (equatorially). The intensity ratio of the unit image will diminish, with definition, detail, and contrast being lost as the distance from the center is increased.
Astigmatism
can be corrected with glasses, contacts, or surgically. The most common surgeries used to correct astigmatism are astigmatic keratotomy (procedures that involve placing a microscopic incision on the eye) and LASIK. The objective of these procedures is to reshape the cornea so it becomes more spherical or uniformly curved.
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